The present invention relates generally to drinking water filtration systems, and particularly to cartridges used in water pitcher filtration units.
Conventional water pitcher filtration units include a pitcher dimensioned for retaining a supply of filtered water, and a funnel disposed within and suspended from an upper end of the pitcher. The funnel defines a volume within the pitcher, into which untreated potable water is poured by the user. A filter cartridge is situated within the funnel, typically at a lowest point to receive water through a cartridge inlet. The cartridge contains a filter media, typically activated carbon and other additives well known in the art. After treatment in the cartridge through gravity flow, the water exits a cartridge outlet and flows into the pitcher volume. The user accesses the pitcher volume for obtaining treated water.
One drawback of conventional pitcher filters is that particles of filter media often escape through openings in the outlet. This is undesirable from the consumer standpoint, since the water appears contaminated. Manufacturers of such cartridges typically address this problem by adding a mesh screen at the base of the cartridge housing near the outlet so that particles of filter media cannot easily escape into the filter volume. However, the inclusion of the screen adds manufacturing material and labor costs.
Another drawback of conventional pitcher filter cartridges is that filter media also may escape through water inlet openings in the upper end of the cartridge. Manufacturers in some cases add screens for preventing this escape, however for many models of conventional cartridges, this unsightly escape of media is still a problem.
Yet another drawback of conventional pitcher filter cartridges is that manufacturing costs are generally considered excessive and should be reduced where possible.